The man who claims to be the world's leading authority on deals made a really stupid one in front of the entire country he hopes to lead. Sad!

Trump agreed to let Cruz give a prime-time speech without having to promise an endorsement. I don't know for sure what Trump got in exchange for that, but I have a guess.

Cruz won enough states that he was entitled to have his name entered for nomination, which would have forced a formal floor contest on Tuesday that Trump wished to avoid, even though Trump would have won it. Cruz didn't enter his name, and Trump gave him a speaking slot without requiring an endorsement.

The Trump campaign knew on Monday that Cruz would not endorse in his speech, according to The New York Times, citing sources from both the Trump and Cruz campaigns.

Even if they were hoping Cruz would change his mind, they had to know by 8:20 p.m. Wednesday that Cruz would not endorse, since that's when the Republican National Convention emailed the full text of the speech to reporters, including the "vote your conscience" line and omitting any endorsement.

So Trump knew Cruz wouldn't endorse, and his campaign could have prepared his loyalists for that fact. And it seems they did, but not in a way that makes any sense: Zeke Miller of Time, among others, reports that Trump campaign "whips" on the convention floor — campaign loyalists whose job is to keep friendly delegates in line — encouraged the booing.

After the speech, Trump's surrogates have been savaging Cruz in the media. Gov. Chris Christie called the speech "selfish." Trump's lawyer, Michael Cohen, said on CNN that the RNC should take retaliatory action against Cruz (and also Gov. John Kasich) for failing to endorse the nominee as they had pledged to do.

I understand the desire to vent. But recriminations against wayward Republicans do nothing to get Trump elected. They only make it harder for Trump to consolidate the votes he needs to win. This is not strategy — it's stupidity.

Trump could have urged his supporters to listen politely and magnanimously to what he knew would be a nonendorsement speech. Or, if the idea of a nonendorsement was too outrageous to bear, he could have denied Cruz a speaking slot. Having Cruz's name entered into nomination would have been less damaging than this mess.

I suspect that Trump and his advisers simply misread the situation: They thought being booed off the stage would be a humiliation for Cruz and did not sufficiently consider how the episode could damage Trump.

This was really, really stupid. It might make you feel like laughing at Trump for his terrible dealmaking skills. But remember, if he becomes president, Donald Trump will have the job of making deals on our behalf — and he is likely to screw them up the way he screwed up this one.